Rotatable insulating bushing



Jan. 15, 1963 B. A. BARENGOLTZ 3,073,891 ROTATABLE INSULATING BUSHINGFiled July 6, 1959 2 Sheets-Sheet 1 i 2 i l I k l J INVENTOR. zz/vuzllziwazrz Y GYM 60m Jan. 15, 1963 B. A. BARENGOLTZ ROTATABLE INSULATINGBUSHING 2 Sheets-Sheet 2 Filed July 6, 1959 A 7" mewsy United StatesPatent Office 3,073,891 RQTATAELE INSULATING Ell Bernard A. Barengoltz,Pittsburgh, Pa., as .gwr

Gravy-Edison This invention relates to encased electrical apparatus andmore particularly to bushing support means for such apparatus.

Mobile substations are widely used by electrical utilities to replacepermanent installations in the event that the damage resulting from aserious fault is not immediately repairable, thereby enabling therestoration of service with a minimum delay. in addition, this type ofequipment is utilized to maintain service during routine maintenance orreplacement of existing substations or to service new customers whilepermanent installations are being installed. Such mobile substationsgenerally include a transformer and its associated switching andprotective equipment which are usually mounted on a highway trailer andmoved by conventional tractors. As a result, such equipment must conformto state highway regulations as to Weight, height and width. Theseregulations generally require that the over-all width of the vehicle,including overhang, shall not exceed some fixed value, generally 96inches. in some instances, however, this width does not allow suihcientelectrical clearance between the terminals of the transformers highvoltage bushings. As a result, the electrical rating of the transformermust be limited or the high voltage bushings must be removed duringtransit.

Removal of the high voltage bushings at the beginning of each tripgenerally involves the following procedure: breaking the transformerseal; removing and storing the transformer oil; removing and crating thehigh voltage bushings; anchoring the high voltage leads; covering thehigh voltage bushing apertures; and purging and filling the transformerwith dry nitrogen. In addition, substantially the reverse of thisprocedure is necessary upon arrival at the point of use. It can thus beseen, therefore, that such removal and replacement is quite costly andtime consuming.

It is an object of the invention to provide a casing for electricapparatus having bushing support means which allows adjustment in theangle and direction of inclination of the bushing relative to thecasing. it is a further object of the invention to provide such abushing support means which is adapted to receive a standard electricalbushing.

It is another object of the invention to provide a casing for electricalapparatus having bushing support means which allows the direction ofinclination of said bushing to be changed with respect to the casing sothat the overall width of the device may be decreased during shipmentwhile the over-all electrical clearance may be increased during use.

It is a still further object of the invention to provide a sealed casingfor electrical apparatus with bushing support means which allows thebushings direction of inclination to be changed While the casing remainssealed.

These and other objects of the invention will become apparent in thedetailed description of the invention taken in conjunction with thedrawings in which:

FIG. 1 shows a mobile substation incorporating the instant invention;

FIGS. 2 and 3 show bushing support means according to the instantinvention and its associated bushing in their operative and shippingpositions respectively;

FIG. 4 shows a top view partly in section taken along when Patented Jan.15, 1963 2 line 4---'.- of PEG. 5 of bushing support means according tothe instant invention; and

FIG. 5 is a side view partly in section taken along line 55 of i6. 4 ofthe bushing support means according to the instant invention.

In general terms, the invention comprises a casing for an electricalapparatus having an opening for receiving an electrical bushing, andbushing support means adjacent said opening and rotatable on said casingfor mounting a bushing said opening with the axis thereof inclinedrelative to the rotational axis of said support means so that rotationof the bushing support means will change the direction and/ or the angleof inclination of the bushing with respect to the casin". in addition,according to another aspect of the invention, the bushing support meansalso includes sealing means disposed between the bushing support meansand the casing so that the casing remains sealed during the rotation ofthe bushing.

in a more specific form of the invention, the opening in said casing isdefined by a cylindrical surface while the bushing support meansincludes a sleeve portion telecopically engaging this surface forrotation therein about an axis substantially parallel to the axis of theopening. The bushing support assembly also includes a mounting plateaflixed to the outer edge of the sleeve member for rotation therewithand being in sliding engagement with the outer surface of the casing.The mounting plate has an aperture formed therein which is eccentricallydisposed relative to the sleeve portion and whose diameter is less thanthe diameter thereof. A tube portion is affixed to the mounting platewith its axis inclined relative to the axis of said sleeve andsurrounding the aperture therein. A support flange is ai'fixed to thesleeve portion and lies in a plane substantially perpendicular to theaxis thereof. Ar'fixed to the support flange is a standard electricalbushing having a mounting flange intermediate its ends and whoseportions on opposite sides of said flange are coaxial. The invention mayalso include stop means which limits the rotation of the bushing supportassembly to a prescribed angle. In addition, the invention may includeclamping means for holding the bushing support means in each of theextremes of its angle of rotation and retaining means afixed to thecasing and slidably engaging the outer surface of the mounting plate forpreventing movement thereof in an axial direction relativeto theopening.

Referring now to the drawings in greater detail FIG. 1 illustrates amobile substation having a trailer, designated generally by the numeralit which is suitably mounted on front and rear on carriages 12 (only oneof which can be seen in the drawing), and which carries an electricaltransformer within a sealed casing Rigidly mounted on transformer casingare two outer tubular extensions 15 and 16 and a central extension 17,upon each of which is mounted a conventional high voltage bushing 13, 19and 26) respectively.

In order to maintain proper electrical clearance between the terminals22 and 23 of the outer electrical bushings 18 and 19 respectively andterminal 24 of central bushing Ztl, it is necessary that these outerbushings extend obliquely from the central bushing during periods ofoperation, as shown by the full lines in FIG. 1 and by FIG. 2. As aresult, the upper ends of bushings 18 and 19 extend beyond the sides ofthe trailer 10 whereby the normal highway width requirements areexceeded. This situation is alleviated by utilizing bushing supportmeans according to the instant invention wherein the outer bushings 18and 19 are moved to a transport position shown by the dotted lines inFIG. 1 and in FIG. 2 so that they are within the outer extremities ofthe trailer 10.

Referring now to FIGS. 4 and 5 the bushing support aoeaeer assemblydesignated by the general reference numeral Ell is mounted on the lefthand tubular extension 15 of the transformer casing 14 and supports aconventional high voltage bushing 18, it being understood that the righthand bushing support assembly is a mirror image of that shown in FIGS. 4and 5. An outwardly extending annular flange 36 surrounds the upper endof tubular extension 15 for supporting an annular bearing and supportmember The juncture between bearing member and flange is sealed by anannular gasket 39 disposed in a circumferential groove 40 formed in thelower surface of hearing member 38. An aperture for receiving bushing isdefined by the inner cylindrical surface 41 of bearing member 38.

The bushing support assembly 30 includes a sleeve member 42 which iscoaxial with and telescopically received in surface 4i and an aperturedmounting plate dd welded to the upper edge of sleeve member 42 and inslidable engagement with the upper surface of bearing member 38. As canbe seen in F185. 4 and 5 the aperture 46 in mounting plate 44 has asmaller diameter than that of sleeve portion 42 and is eccentricallydisposed relative thereto. A tube portion 48 having an inner diameterequal to the diameter of aperture as is welded to the upper surface ofmounting plate 44 and in registry with aperture 46. As shown in FIG. 5the upper and lower edges of tube portion 48 are non-parallel so thatits axis is inclined relative to the axis of the sleeve 42. A supportflange 50 is suitably 'aflixed to the upper edge of tube portion 48 andlies in a plane which is substantially perpendicular to the axisthereof. Surrounding support plate 44 and supported verticallythereaboveby a plurality of spacer members 54 is an annular retainingring 52. A plurality of spaced apart bolts 56, suitably aflixed to thelower surface of retaining ring 52, extend through aligned openings inand suitably aflixed to spacers 54, hearing plate 38 and flange 36 andeach bolt 56 threadably r ceives a nut 58 at its lower end for holdingthe assembly together.

A pair of radially extending shoulders 69 and 62 are disposed onsubstantially opposite sides of support plate 44 to define asemi-circular portion of increased diameter which extends belowretaining ring 52 so that axial movement of bushing support assembly 39is limited. In addition, the shoulders 69 and 62 provide stop engagingmeans which are cooperable upon rotation of the assembly with a stopmember 64 integral with one of the spacers 54 to limit the angle ofrotation of the assembly to substantially 180.

The bushing support assembly 30 is securable to bearing plate 38 in eachof its operative and transport positions by means of a plurality ofbolts as which extend through clearance holes 74} in plate member 44 andwhich threadably engage corresponding tapped holes 72 in bearing member38. A continuous annular gasket 73, disposed within an annular groove 74on the upper surface of bearing plate 38, provides the major seal forthe device when the assembly is in either of these positions. In orderto maintain the casing 14 in a sealed condition during rotation of thebushing support assembly 3%, a pair of annular gaskets 76 are disposedin a pair of axially spaced circumferential grooves 78 formed in theouter surface of sleeve portion 42 and compressed between these groovesand the annular surface 41 of bearing plate 38.

The high voltage bushing 1% is of a conventional type and includes aconductive central stud 39 surrounded by a sleeve of insulating material82, a shell $3 of suitable insulatingmaterial such as porcelain and ametallic mounting flange 84 suitably secured to the outer surface ofsaid insulating sleeve by means of a metallic collar 85. A plurality ofbolts 86secure mounting flange 34 of bushing'18 to the support flangeSt) of bushing support assembly 30. 'It can be seen from FIG. 5 that theaxis 37 of bushing 18 will be substantially coincident to the axis oftubular portion 48 so that said bushing assembly will be A inclinedrelative to the axis of rotation 83 of the bushing support assembly 31?.In addition, it can be seen that since the support assembly 3% isadapted to receive a bushing 13 whose portions on either side ofmounting flange 34 are coaxial, there is no necessity to utilize amodified type of angular bushing in this assembly.

An annular gasket 39 is disposed between support flange 5t} and mountingflange 84 to provide a hermetic seal therebetween. To facilitaterotation of the assembly a wrench member 9t? is bolted to the exteriorsurface of support flange 5% and is adapted to telescopically receive astandard extension member 92.

While the transformer is in use, bushing 13 will be in the positionshown in full in FIGS. 1, 4 and 5 and in FIG. 2, with the radiallyextending shoulder 6-13 in engagement with stop 64. When it is desiredto move the transformer to another location, bolts 68 are removedfreeing the bushing support assembly 3% for rotation relative to thetubular bushing support means 15. In order to facilitate freedom ofmovement between support plate 44 and bushing ring aset screw 94 isprovided in each of a plurality of threaded holes in support plate 44and each bears against the upper surface of bearing member Rotation ofset screws 94 moves support plate 44 away from hearing member 3 5 tofacilitate movement therebetween. Extension 92 is then placed over theend of wrench Ed and the assembly is rotated in a clockwise direction asviewed in FIG. 4 from the position shown full in FIGS. 1, 4 and 5 and inFIG. 2 to the position shown dotted in FIGS. 1, 4 and 5 and in FIG. 3.This brings radially extending shoulder 62 into engagement with stop 64and openings 7 in support plate 44 into registry with different ones ofthe tapped holes 72 in bearing assembly 33. Bolts 68 are then reinsertedand the seal between the upper surface d5 of bearing plate 38 and lowersurface of support plate 44 i then reestablished. When the assemblyreaches its destination bolts 63 are again removed and the assembly isrotated in a counterclockwise direction as viewed in FIG. 2 from theposition shown dotted in FIGS. 1, 4 and S and in FIG. 3 to the positionshown full in FIGS. 1, 4 and 5 and in FIG. 2, whereupon bolts 63 areagain reinserted and the device is again ready for operation.

It can thus be seen that by mounting the outer bushings 13 and 19 insuch a manner that their axes are inclined relative the rotational axesof the support assemblies, the direction and angle of inclination of thebushing relative to the transformer casing 14 can be changed. In thismanner the upper ends 22 and 23 of these bushings, which for properelectrical clearance must extend beyond the sides of the trailer itduring operation, may be moved within the outer extremities thereof sothat its over-all width is within normal highway clearance requirements.In addition by mounting these outer bushings eccentrically relative totheir axes of rotation they may also be physically displaced inwardlyupon rotation. Also, the bushing support assembly according to theinstant invention is adapted to receive a standard bushing so that theadditional expense involved in the use of a non-standard bushing is notencountered.

While the invention is disclosed with relation to mobile substations, itwill be understood by those skilled in the art that it has applicationto normally stationary devices as well. For example such bushing supportassemblies could be utilized on conventional power type transformers sothat the necessity of removing the bushings during shipment from thefactory is eliminated.

Although only a single embodiment of the instant invention is shown anddescribed a number of modifications will become apparent to thoseskilled in the art once applicants inventive concept is known. It is,therefore, intended to cover in the appended claims all suchmodifications which fall within the true spirit of the invention.

I claim:

1. In combination with a casing for an electrical apparatus having anopening therein, the margin of said opening defining a cylindricalsurface, a rotatable bushing support assembly having a sleeve portiontelescopically engaging said surface for rotation therein about an axissubstantially parallel to the axis thereof, a mounting plate aifixed tothe outer edge of said sleeve portion and overlying the portion of saidcasing defining said opening for rotation with said sleeve portion andhaving an aperture registering with said opening, a straight, outwardlyextending tube portion aflixed to said mounting plate and surroundingsaid aperture, the axis of said tube portion being inclined relative tothe axis of said sleeve portion, an annular support flange affixed tosaid tube portion and lying in a plane substantially perpendicular tothe axis thereof, a straight electrical insulating bushing having amounting flange intermediate its ends, clamping means for aflixing saidmounting flange to said support flange, said straight insulating bushingso aflixed to said support flange extending coaxially through saidstraight tube portion and through said aperture and into said openingand the portions of said bushing on either side of said mounting flangebeing substantially coaxial, said mounting plate being selectivelyrotatable between first and second positions whereby rotation of saidsleeve portion and mounting plate will change the position of saidbushing with respect to said casing.

2. in the combination defined by claim 1 wherein said sleeve portion hasa cylindrical surface opposed to said cylindrical surface defined by themargin of said opening, one of said o posed cylindrical surfaces has atleast one circumferen" groove therein, and including resilientcontinuous gasket means within said groove compressed between saidopposed cylindrical surfaces for hermetically sealing between saidbushing support assembly and said casing during rotation of saidmounting plate, and means engaging s d casing for releasably clampingsaid mounting plate in said first and second positions.

3. in combination with a sealed casing for an electrical apparatushaving at least one opening formed therein, wherein the margin of saidopening defines a cylindrical surface, a bushing support assembly havinga sleeve portion telescopically engaging said surface for rotationtherein about axis substantially parallel to the axis thereof, amounting plate aflixed to the outer edge of said sleeve portion andslidably engaging the outer surface of said casing for rotation withsaid sleeve portion, a tube portion affixed to said mounting plate andsurrounding said aperture, the axis of said tube portion being inclinedrelative to the axis of said sleeve portion, a support afiixed to saidtube portion and lying in a plane substantially perpendicular to theaxis thereof, an electrical bushing having a mounting flangeintermediate its ends, clamping means for affixing said mounting flangeto said support flange, the portions of said bushing on either side ofsaid mounting flange being coaxial whereby rotation of said bushingsupport means will change the direction of inclination of said bushingwith respect to said casing, and retaining means afiixed to said casingand slidably en aging the upper surface of said mounting plate forpreventing movement of said support assembly axially of said opening.

4. in combination with a sealed casing for an electrical apparatushaving at least one opening formed therein, wherein the margin of saidopening defines a cylindrical surface, a bushing support assembly havinga sleeve portion telescopically engaging said surface for rotationtherein about an axis substantially parallel to the axis thereof, amounting plate ailixed to the outer edge of said sleeve portion andslidably engaging the outer surface of said casing for rotation withsaid sleeve portion, said mounting plate having an aperture formedtherein which is eccentrically disposed relative to said sleeve andhaving a diameter less than the iarneter thereof, a tube portion affixedto said mounting plate and surrounding said aperture, the axis of saidtube portion being inclined iii relative to axis of said sleeve portion,a support flange afiixed to said tube portion and lying in a planesubstantially perpendicular to the axis thereof, an electrical bushinghaving a mounting flange intermediate its ends, clamping means foraflixing said mounting flange to d support flange, the portions of saidbushing on 7 side of said mounting flange being coaxial, stop meansmounted on the surface of said casing and disposed adjacent the edge ofsaid mounting plate, said men s plate having spaced apart stop engagingmeans c rotation of said bushing support means is limited to aprescribed an clamping means engaging C said casing and said bushingsupport means for holding the latter in each of the extremes of itsangle of rotation, retaining means afflxed to said casing and slidablyengagup or surface of said mounting plate for preventing niovem of saidsupport assembly axially of said opening, and gasket means disposedbetween sleeve portion and said 0; ening so that said casing remainssealed during rota n of said assembly.

5. In combination, an enclosing casing for electrical s mounted onwheels for transportation and havions extending generally in thedirection of transportation, said casing having a pair of horizontallysp ed apart circular openings in a portion thereof genera, y transverseto said side portions, straight elongated insulating bushing in saidopenings, means mounted on S l "-d casing adjacent opening for rotatablysupportthe corresponding bus ing in said opening, each of d meansincluding a sleeve portion, an annular mounting plate portion, and anoutwardly extending straight bular portion secured together with theapertures therein ster and re ister with said opening, said sleeveortion telescopically engaging the margin of said circular rotationtherein about the axis of said opensaid annular mounting plate portionoverlying the ortion of said casing defining said opening and beingnixed to the outer end of said sleeve portion for rotaion there. a aboutsaid axis of said opening and said straight tubular portion beingaffixed to said mounting plate portion w 1 its axis oblique to the saidaxis of rotation of said sleeve and mounting plate portions, an annularsupport flange on said tubular portion perpendicular to the axisthereof, said straight insulating bushing extending through theregistering apertures in said sleeve, mounting plate and tubularportions and being coaxial with said tubular portion and having amounting flange intermediate its ends adjacent said support flange,means for clamping said mounting flange against said support flange, theportions of said insulating bushing on opposite sides of said mountingflange being coaxial, each said support means being selectivelyrotatable between first and second positions and rotation of saidsupport means between said first and second positions displacing theoutward end of said bushing in a direction generally transverse to saiddirection of transportation, rotation'of both said support means fromsaid second to said first positions displacing the outward ends of saidbushings laterally beyond said casing side portions and increasing theelectrical clearance between the outward ends of said bushings androtation of said support means from said first to said second positionsmoving said outward bushin ends laterally inward of said opposed casingside walls and reducing the overall dimensions of said apparatus.

6 in combination, an enclosin casing for electrical apparatus mounted onwheels for transportation and having a pair of horizontally spaced apartopenings in a portion thereof generally transverse to the direction oftransportation, whereby said openings are spaced apart in a directionacross the width of a road along which said casing is transported,elongated straight insulating bushings disposed in said openings, meansmounted on said casing adjacent each said opening for rotatably mountingthe corresponding bushing in said opening, each said 9 and having anaperture therethrough and means for mounting said straight bushing onsaid member so it extends through said aperture and into said generallytubular portion with its axis inclined to the axis of rotation of saidmember, said bushing having a first straight portion extending from saidmember outwardly of said casing coaxial with a second straight portionextending from said member into said generally tubular portion, rotationof said member displacing the outward end of said bushing in a directiongenerally transverse to the direction of transportation, said membersbeing selectively rotatable betwen a first position wherein the spacingbetween the outward end of said bushings associated with said twooutward generally tubular portions is greater than the dimension of saidcasing in a direction generally transverse to said direction oftransportation and a second position wherein said spacing is less thansaid dimension of said casing.

References Cited in the file of this patent UNITED STATES PATENTS979,840 Goddard Dec. 27, 1910 1,389,542 Werely Aug. 30, 1921 1,414,174Campos Apr. 25, 1922 1,605,507 Burke Nov. 2, 1926 1,777,071 BurnhamSept, 30, 1930 2,295,416 Madison Sept. 8, 1942 2,354,191 Bennett July25, 1944 2,427,184 Bilodeau Sept. 9, 1947 2,889,396 Boden et a1 June 2,1959 FOREIGN PATENTS 762,804 Germany Jan. 19, 1953

6. IN COMBINATION, AN ENCLOSING CASING FOR ELECTRICAL APPARATUS MOUNTEDON WHEELS FOR TRANSPORTATION AND HAVING A PAIR OF HORIZONTALLY SPACEDAPART OPENINGS IN A PORTION THEREOF GENERALLY TRANSVERSE TO THEDIRECTION OF TRANSPORTATION, WHEREBY SAID OPENINGS ARE SPACED APART IN ADIRECTION ACROSS THE WIDTH OF A ROAD ALONG WHICH SAID CASING ISTRANSPORTED, ELONGATED STRAIGHT INSULATING BUSHINGS DISPOSED IN SAIDOPENINGS, MEANS MOUNTED ON SAID CASING ADJACENT EACH SAID OPENING FORROTATABLY MOUNTING THE CORRESPONDING BUSHING IN SAID OPENING, EACH SAIDMEANS INCLUDING A MEMBER CLOSING SAID OPENING AND HAVING AN APERTURETHEREIN REGISTERING WITH SAID OPENING AND SAID MEMBER BEING ROTATABLEABOUT THE AXIS OF SAID OPENING AND MEANS ON SAID MEMBER AND ENGAGINGSAID BUSHING INTERMEDIATE ITS ENDS FOR MOUNTING SAID BUSHING WITH ITSAXIS INCLINED TO SAID AXIS OF SAID OPENING AND ALSO INCLINED TO THE AXISOF ROTATION OF SAID MEMBER, SAID BUSHING SO MOUNTED ON SAID MEMBEREXTENDING THROUGH SAID APERTURE AND INTO SAID OPENING AND HAVING A FIRSTSTRAIGHT PORTION EXTENDING OUTWARDLY FROM SAID CASING COAXIAL WITH ASECOND STRAIGHT PORTION EXTENDING INWARDLY OF SAID CASING AND INTO SAIDOPENING, SAID MEMBER BEING SELECTIVELY ROTATABLE BETWEEN FIRST ANDSECOND POSITIONS AND ROTATION OF SAID SUPPORT MEANS BETWEEN SAID FIRSTAND SECOND POSITIONS DISPLACING THE OUTWARD END OF SAID BUSHING IN ADIRECTION GENERALLY TRANSVERSE TO SAID DIRECTION OF TRANSPORTATION ANDVARYING THE SPACING BETWEEN THE OUTWARD END OF SAID BUSHING AND THEOUTWARD END OF THE OTHER BUSHING IN A DIRECTION ACROSS THE WIDTH OF SAIDROAD ALONG WHICH SAID CASING IS TRANSPORTED.